I also apologize. We got carried away in our own search. Awesome boxes, by the way. Did you make those? I've never seen anything like that design.
Given the fact that you already have the subwoofer and amp for the peerless setup, I would recommend building what you have. You can always build another later and compare. The peerless is a well-tested driver with a solid reputation.
From the Peerless Website:
Conclusion for closed box subwoofer:
From the above simulations it can be concluded that even with a very powerful amplifier of 300 W it is not possible to achieve over 100 dB at 25 Hz.
Using a larger cabinet or counting on the bass boost of all living room environments with the boundaries contributing to amplification of the lowest frequencies a very good transient response can be achieved with the sealed enclosure.
Box data:
Type: Sealed
Volume: 30 l
Qt: 0,48
Note: this is for 30L, which is about 1 Cubic foot. Your boxes are 2 cubic feet and would require different modeling.
Conclusion and data for the vented system:
Using the 12" XLS driver in a vented cabinet can produce some high sound pressures and low distortion is possible with a high pass filter and good port design.
It has been shown that a high pass filter for the system is highly recommended to reduce the excursion below tuning.
Vented cabinet data:
Total volume: 40 litre
Port diameter: Ø90 mm (double flared recommended)
Port length: 510 mm
Tuning frequency: 30 Hz
High pass filter (highly recommended):
Q: 0.7
Fo: 20 Hz
Conclusion for Passive radiator system:
Special considerations regarding overloading of the passive radiator is needed for passive radiator systems. Careful selection of limiting circuits and tuning frequency is needed to avoid unwanted noises from the system.
It has been shown that the tuning of the box is possible but that the user need to invest some time in adjusting the filters and limiters to achieve the goal. A high pass filter is highly recommended like used for the vented system above.
Passive radiator system data:
Total volume: 35 litre
XLS 12" slave with 625g Mms Order Id 830549
Tuning frequency: 20 Hz
High pass filter:
Cut off frequency: 17 Hz
Q: 0,7
- http://www.tymphany.com/papers/appxls12b.htm
Without a Linkwitz Transform circuit, the Rythmik will extend much further than the peerless and have greater output.
The Zaph design is also very solid. I think you will find just about any bookshelf to work well with a subwoofer if the bookshelf can comfortably extend down below 80HZ, as the Zaph seems to do.
Given that the mains and sub will be driven in a HT environment, I don't think you need to worry about how well the actual drivers work together. If they were combined in the same cabinet with a shared amplifier, that would be more relevant. In this case, your receiver's crossover will segregate the two drivers.
I think the question at hand is not how well the drivers will integrate, but what configuration will work best. The Zaph design has notes for both sealed and ported/vented configurations - each with a different characteristic roll-off. The subwoofer design (sealed, vented, IB) that you choose will also have a certain characteristic high-pass roll-off.
The Rythmik Design can be ordered with either a 12dB or 24dB high-pass filter. Once you have decided on your mains configuration, you can call Brian to determine which configuration will integrate best. I am going to go with the 12dB roll-off to integrate with a sealed mains setup, but your tastes and room may need a different optimum selection.
The Rythmik has another advantage - the selectable dampening and extension switches. These will allow you to further customize your response and output once you actually have the sub in your room. This selectability, combined with the greater extension, leans in favor of the Rythmik.
Now, given that I have yet to hear either driver, your judgement is best. Try to seek out someone in your area that has built one or both of these so you can hear them.
Again, sorry for the hijack.